Many space vehicles, generally use a liquid propellant which is stored in storage tanks and fed into engines during take off and flight in space. The liquid must be moved from the storage tanks to the engine in an efficient manner. First, vapor or gas cannot be allowed to enter the engines in any great amount or too early in the ignition process. If gas is introduced into the engines, it may cause a stall or other malfunctioning of the engine that may increase the possibility of engine failure. It is generally known in the art to provide a device that is be placed in the propellant storage tanks which will reduce the acquisition of gas into the engine. Second, it is desirable to empty the storage tanks as completely as possible during an engine burn and flight to reduce re-entry weight and increase vehicle payload. Typically, a portion of liquid propellant still remains in the tank, thereby increasing the vehicle weight and reducing the maximum payload of the vehicle.
One solution to vapor ingestion is to provide a screen that encompasses the interior area of the tank or at least a portion thereof. Therefore, fluid is wicked through the screens by capillary action, and vapor or gas bubbles are prevented from flowing through the screens by the bubble point pressure of the fluid screen system. Screen systems are made most advantageous only for storage tanks being used in low gravity and are less useful in environments where significant gravity is present. Additionally, the screen systems typically cannot be used with certain liquid propellants such as hydrogen peroxide due to material incompatibility between H2O2 and typical screen materials. The increased surface area of the screens adds more area for chemical reactions where the liquid propellant may decompose.
Other systems provide vanes extending a distance from the sump of the tank towards the walls of the storage tank. These vanes help bring liquid propellants to the outflow area of the storage tank through capillary action. Furthermore, the vanes help reduce the ingestion of gas bubbles into the engine of the vehicle. The vanes used in known vapor ingestion suppression systems, however, are for very low flow rates and cannot provide substantial vapor ingestion suppression at the higher flow rates of many reusable space craft.
Thus, the generally known anti-vapor ingestion systems include several drawbacks. Additionally, known systems allow too much fuel to be left in the storage tanks thereby decreasing the efficient use of the fuel stored in the tanks and decreasing the payload for a similarly sized tank and vehicle. Additionally, the known systems increase the breakdown of certain propellant fluids into gas and non-fuel or inert substances. Therefore, there is a need in the art for a device that will allow for anti-vortexing of the fuel as it leaves the tank, and to increase ingestion of liquid propellant into the sump and outlet, thereby increasing the efficiency of the storage tanks and decreasing the possible ingestion of gases.